Control pin and spout system for heating metal casting distribution spout configurations

ABSTRACT

A control pin system, including an apparatus and method, for use in controlling the flow of molten metal in a molten metal distribution system for casting, with some aspects of the control pin including: a control pin body with an internal cavity and an outer surface, wherein the outer surface is sized and configured to operatively interact with an internal surface of a spout to effectively control the flow of molten metal through a spout aperture; and a heater element within the internal cavity of the control pin body. In other embodiments, the heater may be located within the spout body and transferring heat to the control pin.

CROSS REFERENCE TO RELATED APPLICATION

This application does not claim priority from any other application.

TECHNICAL FIELD

This invention pertains to a control pin and spout system forpre-heating and/or heating the metal casting distribution spoutconfigurations for pouring non-ferrous metal such as molten aluminuminto casting molds; more particularly, a metal flow control pin and/orspout configuration which provides heat before, during and/or aftercasting at the metal flow control pin and/or spout.

BACKGROUND OF THE INVENTION

Metal ingots, billets and other castparts may be formed by a castingprocess which utilizes a vertically oriented mold situated above a largecasting pit beneath the floor level of the metal casting facility,although this invention may also be utilized in horizontal molds. Thelower component of the vertical casting mold is a starting block. Whenthe casting process begins, the starting blocks are in their upward-mostposition and in the molds. As molten metal is poured into the mold boreor cavity and cooled (typically by water), the starting block is slowlylowered at a pre-determined rate by a hydraulic cylinder or otherdevice. As the starting block is lowered, solidified metal or aluminumemerges from the bottom of the mold and ingots, rounds or billets ofvarious geometries are formed, which may also be referred to herein ascastparts.

While the invention applies to the casting of metals in general,including without limitation aluminum, brass, lead, zinc, magnesium,copper, steel, etc., the examples given and preferred embodimentdisclosed may be directed to aluminum, and therefore the term aluminumor molten metal may be used throughout for consistency even though theinvention applies more generally to metals.

While there are numerous ways to achieve and configure a verticalcasting arrangement, FIG. 1 illustrates one example. In FIG. 1, thevertical casting of aluminum generally occurs beneath the elevationlevel of the factory floor in a casting pit. Directly beneath thecasting pit floor 101 a is a caisson 103, in which the barrel 102 forthe hydraulic cylinder is placed.

As shown in FIG. 1, the components of the lower portion of a typicalvertical aluminum casting apparatus, shown within a casting pit 101 anda caisson 103, are a hydraulic cylinder barrel 102, a ram 106, amounting base housing 105, and a starting block base 114 (also referredto as a starting head or bottom block), all shown at elevations belowthe casting facility floor 104.

The mounting base housing 105 is mounted to the floor 101 a of thecasting pit 101, below which is the caisson 103. The caisson 103 isdefined by its side walls 103 b and its floor 103 a.

A typical mold table assembly 110 is also shown in FIG. 1, which can betilted as shown by hydraulic cylinder 111 pushing mold table tilt arm110 a such that it pivots about point 112 and thereby raises and rotatesthe main casting frame assembly, as shown in FIG. 1. There are also moldtable carriages which allow the mold table assemblies to be moved to andfrom the casting position above the casting pit.

FIG. 1 further shows the starting block base 114 partially descendedinto the casting pit 101 with castpart or ingot 113 being partiallyformed. Ingot 113 is on the starting block base 114, which may include astarting head or bottom block, which usually (but not always) sits onthe starting block base 114, all of which are known in the art and neednot therefore be shown or described in greater detail. While the termstarting block is used for item 114, it should be noted that the termsbottom block and starting head are also used in the industry to refer toitem 114, bottom block typically used when an ingot is being cast andstarting head when a billet is being cast.

When hydraulic fluid is introduced into the hydraulic cylinder atsufficient pressure, the ram 106, and consequently the starting block114, are raised to the desired elevation start level for the castingprocess, which is when the starting blocks are within the mold tableassembly 110.

The lowering of the starting block 114 may be accomplished by any one ofa number of different means or mechanisms, such as hydraulic as shown,ball screws or cable systems. The embodiment shown in the figure mayutilize a metering of the hydraulic fluid from the hydraulic cylinder ata pre-determined rate, thereby lowering the ram 106 and consequently thestarting block at a pre-determined and controlled rate (which may alsobe subject to manual intervention by operators or controllers). The moldis controllably cooled during the process to assist in thesolidification of the emerging ingots or billets, typically using watercooling means.

There are numerous mold and casting technologies that fit into moldtables, and no one in particular is required to practice the variousembodiments of this invention, since they are known by those of ordinaryskill in the art.

The upper side of the typical mold table operatively connects to, orinteracts with, the metal distribution system. The typical mold tablealso operatively connects to the molds which it houses.

When metal is cast using a continuous cast vertical mold, the moltenmetal is cooled in the mold and continuously emerges from the lower endof the mold as the starting block base is lowered. The emerging billet,ingot or other configuration is intended to be sufficiently solidifiedsuch that it maintains its desired shape. Below that, there is also amold air cavity between the emerging solidified metal and the lowerportion of the mold and related equipment.

After a particular cast is completed, as described above, the mold tableis typically tilted upward and away from the top of the casting pit, asshown in FIG. 1.

It is generally desired to avoid any solidification of the molten metalin the distribution system and substantial efforts are employed to avoidsolidification as it may result in blockages and require that casts beaborted, which consequently results in undesirable down time of theproduction of the non-ferrous metal. In particular metal distributionsystems, spouts are utilized to distribute and pour molten metal such asaluminum into molds, including molds which produce castparts referred toas ingots. Some of these distribution systems may be comprised oftroughs which distribute molten metal to the necessary molds, all ofwhich are generally known and used in the industry. A series of dams andother blocking devices may be used to initiate, stop or otherwisecontrol the flow to some or all of the molds, in aspects of thisinvention.

It is the control pins that are generally used to control the flow ofthe molten metal as delivered to the spouts from the metal distributionsystem, although the control pins may also be utilized for some part ofthe starting and stopping of molten metal flow through the spouts andinto the molds. Due to several factors such as the surface area tovolume and temperature of metal, the spout areas present an area wherethe molten metal tends to solidify if the process is not sufficientlycontrolled. Solidification of a sufficient amount of molten metal at thespout area results in the uneven flow of molten metal into one moldversus another in a mold table with multiple molds and may lead toblockage of the spout and/or the need to abort a cast before it iscompleted.

Heated spout pins or control pins are generally placed within theaperture in the spout to block the aperture or plug the hole whendesired, normally at the beginning and at the end of the cast. At thebeginning of the cast for instance, the control pins are placed withinthe apertures in the spouts to block the flow of molten metal to themolds until the desired time, such as when all molds can be suppliedapproximately simultaneously. These control pins are then moved tochange the aperture size to vary metal flow rates over the length ofcast. At the end of a cast on a mold table with a plurality of molds,there would generally be a plurality of spouts and personnel wouldgenerally hurry to remove the control pins in each spout to avoid moltenmetal solidifying in the spout and creating undesirable issues for thenext cast as the spout refractory material is typically at a temperaturewhich would cause the solidification of the metal at that interface. Insome molten metal level control systems, the spout is plugged until thelaunder is full and then the control pins are removed and the spoutsopened, there by controlling the metal flow as shown in FIG. 8.

It is therefore an objective of some embodiments of this invention toprovide a mechanism to avoid the solidification of the molten metal ator on the spout surface and/or at or on the surface of the control spoutpins.

Some advantages that may be achieved by different embodiments or aspectsof this invention, although not required, may be the reduction orelimination of freeze ups due to solidification of molten metal. Threesteps result in a shutdown of the system, cleaning of the freeze up areaand then re-starting or initiating the casting process (which takesunnecessary time and requires unnecessary expense). It may for examplein some applications require a twenty-five minute cool down periodbefore action may be taken at the control pin and spout location andthen another forty-five minutes to reheat to prepare for the nextcasting. Embodiments of this invention may also eliminate heating ovenswhich may be used in prior art to maintain temperatures at a sufficientlevel.

Another possible advantage in the utilization of embodiments of thisinvention is that if a thermocouple is used, data provided by thethermocouple readings may give an indication of the health or status ofthe control pin and spout, allowing preventative maintenance to beperformed, which should reduce unexpected failures in some cases.

Another possible advantage in some embodiments of this invention is thesaving of time, namely time in dealing with spout heaters. A furtheradvantage of embodiments of this invention may be that better controlmay be maintained over the process at temperatures inherent in theprocess. A still further advantage of embodiments of this invention isthe reduction of personnel time in and around the molds to deal withsome or all of the problems described above and which may be eliminatedby this invention.

Although embodiments and aspects of this invention are directed to theobjective(s) stated above, and/or to some of the advantages statedabove, it will be appreciated by those of ordinary skill in the art thatthis invention is not limited to any one objective or any one or moreadvantages.

Other objects, features, and advantages of this invention will appearfrom the specification, claims, and accompanying drawings which form apart hereof. In carrying out the objects of this invention, it is to beunderstood that its essential features are susceptible to change indesign and structural arrangement, with only one practicle, andpreferred embodiment being illustrated in the accompanying drawings, asrequired.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

FIG. 1 is an elevation view of a prior art vertical casting pit, caissonand metal casting apparatus;

FIG. 2 is a cross-sectional view of a prior art control pinconfiguration, illustrating a solid control pin in the spout of adistribution trough, in one example of a semi-continuous metaldistribution and casting system;

FIG. 3 is a cross-sectional view of one embodiment of a control pin andspout system in a semi-continuous metal distribution and casting systemcontemplated by this invention;

FIG. 4 is the cross-sectional view of one embodiment of the control pinand spout system illustrated in FIG. 3, only wherein the control pin hasbeen removed from blocking molten metal flow through the spout;

FIG. 5 is a perspective cross-sectional view of an embodiment of acontrol system spout pin which may be utilized as contemplated by thisinvention;

FIG. 6 is a cross-sectional view of an embodiment of a control systemspout pin which may be utilized as contemplated by this invention;

FIG. 6A is portion 6A from FIG. 6 of the embodiment of the controlsystem spout pin which may be utilized as contemplated by thisinvention;

FIG. 6B is portion 6B from FIG. 6 of the embodiment of the controlsystem spout pin which may be utilized as contemplated by thisinvention;

FIG. 7 is a cross-sectional view of an embodiment of a control systemspout which may be utilized as contemplated by this invention, whereinthe spout includes a heating element to provide heat;

FIG. 7A is detail 7A from FIG. 7;

FIG. 8 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe top portion of the spout;

FIG. 9 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe middle portion of the spout;

FIG. 10 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe lower portion of the spout;

FIG. 11 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe middle portion of the spout;

FIG. 12 is an exemplary elevation cross-sectional view of one example ofanother embodiment of this invention illustrating heat transfer from thecontrol pin to the spout; and

FIG. 13 is an exemplary elevation cross-sectional view of one example ofanother embodiment of this invention illustrating heat transfer from thespout to the control pin.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Many of the fastening, connection, manufacturing and other means andcomponents utilized in this invention are widely known and used in thefield of the invention described, and their exact nature or type is notnecessary for an understanding and use of the invention by a personskilled in the art or science; therefore, they will not be discussed insignificant detail. Furthermore, the various components shown ordescribed herein for any specific application of this invention can bevaried or altered as anticipated by this invention and the practice of aspecific application or embodiment of any element may already be widelyknown or used in the art or by persons skilled in the art or science;therefore, each will not be discussed in significant detail.

The terms “a,” “an,” and “the” as used in the claims herein are used inconformance with long-standing claim drafting practice and not in alimiting way. Unless specifically set forth herein, the terms “a”, “an”,and “the” are not limited to one of such elements, but instead mean “atleast one.”

FIG. 1 is an elevation view of a typical prior art vertical casting pit,caisson and metal casting apparatus, and is described in more detailabove.

FIG. 2 is a cross-sectional view of a prior art control pinconfiguration, illustrating a solid control pin in the spout of adistribution trough, in one example of a semi-continuous metaldistribution and casting system. FIG. 2 illustrates molten metaldistribution launder 125, molten metal distribution trough 120,refractory material 122 defining molten metal distribution trough 120,launder framework 123, spout 127 and control arm 132. The cast part moldframework 129 is shown above bottom block 130 before the beginning of acast.

It will be appreciated by those of ordinary skill in the art the extentto which cooler surfaces, when interfacing with molten metal, may causea cooling or solidification of the molten metal on the surface of thematerial, which would typically be a refractory material. For instancethe metal distribution trough 120 shown in FIG. 2 is made of any one ofa number of refractory materials designed to withstand the high heatpresent in molten metal casting systems. Prior art control pins 121 aregenerally made of a refractory material and solid core, although sometubular or hollow pins such as that disclosed in U.S. Pat. No.7,165,757, issued Jan. 23, 2007, are constructed or comprised ofdifferent materials and combinations. The lower end 121 a of control pin121 is shown inserted in spout 127 to control the flow of metalthere-through.

In a typical casting facility there would be trough configurations abovea plurality of molten metal casting molds with a plurality of controlpins 121 inserted in spouts such as spout 127 to control the flow ofmolten metal provided into the trough configuration. Once the moltenmetal is provided throughout the trough system, it is generallydesirable to simultaneously provide the molten metal to the moldsthrough the spout, and this is accomplished through known distributionsystem flow control methods, such as dams and other devices. The moltenmetal then flows through the control pin 121 and spout 127configuration, with the control pin 121 being utilized to control theflow of the molten metal It can be seen from the configuration of thespout 127 and control pin 121 how blockages may occur in and around thespout 127, the aperture in the spout and the control pin 121.

It will be appreciated by those of ordinary skill in the industry thatthe term “control pin” or “pin” is used to identify the componentreferred to herein. For purposes of this invention that term will beused, however, it is not used to limit the component to any particularshape, geometry or configuration—but instead any such configurationutilized to control or manage the flow of molten metal through the spoutmay be contemplated in aspects of this invention. Some examples areshown in later figures, but they are by no means a limitation on thedifferent shapes or configurations that may be utilized to practicedifferent embodiments and aspects of this invention. In some cases thepin may be referred to as a plug, but many do not however completelyplug the flow of molten metal, but instead control it.

FIG. 3 is a cross-sectional view of one embodiment of a control pin 143contemplated by this invention, inserted into spout 144 and partially orwholly blocking the flow of molten metal 140 through the aperture. FIG.3 illustrates molten metal distribution launder 138, launder framework123, trough 139 defined by refractory material 122 and the inner surface147 of the molten metal distribution trough 139, with molten metal 140contained therein, and control arm 132.

FIG. 3 further illustrates one example of an embodiment of a control pin143 contemplated by this invention inserted into spout 144 and blockingthe flow of molten metal 140 through the aperture in spout 144. Lines145 illustrate the flow of heat from control pin 143 into spout 144 andpartially into the trough area, which tends to maintain an outer surfaceof control pin 143 and a suitable temperature such that molten metaldoes not solidify on that outer surface, or on the inner surface withinthe aperture in spout 144. More detail on control pin 143 is provided inlater figures.

FIG. 3 further illustrates how heat provided from within the interiorcavity of control pin 143 will not only heat the external or outersurface of control pin 143, but may also be configured or designed toalso transfer heat to the spout 144 and internal surface of spout 144.This has the effect of reducing the tendency for molten metal tosolidify on the outer surface of the control pin 143 and on the innersurface of spout 144.

The hollow control pin configuration illustrated in the embodiment ofthe invention shown in FIG. 3 may be constructed out of any one of anumber of different refractory materials, with a material such as one atleast partially comprised of a composite ceramic material which includesa fibrous reinforcing material embedded within a ceramic matrix such asdisclosed in U.S. Pat. No. 7,165,757.

The vertical movement of control pin 143 may be accomplished by any oneof a number of different mechanisms known or yet to be discovered in theart. One example of such is a control system which includes a linearactuator work in combination with a fulcrum.

The heating may be provided by any one of a number of mechanisms, meansor sources within the contemplation of this invention, including withoutlimitation, electric resistance heat as shown, inductive heating, hotair or gas flame heating, and also a chemical reaction of some sort, aswill be appreciated by those of ordinary skill.

FIG. 4 is the cross-sectional view of one embodiment of the control pinand spout system illustrated in FIG. 3, only wherein the control pin hasbeen removed from blocking molten metal flow through the spout. FIG. 4illustrates control arm 132 rotated to lift control pin 143 asillustrated by arrow 150 such that control pin 143 is no longer blockingthe molten metal in molten metal distribution trough 139 from flowingthrough the internal passageway through spout 144, as shown by metalflow arrows 152. The lower end 143 a of control pin 143 is shown abovethe entry opening to spout 144. All other items shown in FIG. 4 are likeitems to those shown in FIG. 3 and will not therefore be described infurther detail here.

FIGS. 3 and 4 further illustrate how control pin 143 may be housed,secured or held by control pin holder 137 in order to secure a hollow ortubular control pin such as control pin 143 for vertical movement andlocation, and to help facilitate the providing of heating elements suchas heating coils, and heating control elements such as thermocouples,within the interior cavity of hollow control pin 143. Control pin holder137 will have an internal cavity which generally corresponds to theexternal surface and configuration of control pin 143 to allow it to besecured thereto by any one of a number of different mechanisms, such asfor example with a mechanical pin, or by placing glue there-between.

Those of ordinary skill in the art understand that in normal prior artoperations, there is a rush to place the prior art control pins intoplace within the spout, and to start the cast, before cooling of the pinand spout occurs so that solidification does not result in castingdelays. In some prior art systems, an external gas spout heater isutilized to heat the spout in an attempt to prevent or reducesolidification of molten metal in the spout area and embodiments of thisinvention will allow the elimination of spout heaters in the moltenmetal systems.

It may be desirable or preferred in some embodiments of this inventionto discontinue providing heat through the control pin once casting orpouring has commenced because the molten metal will provide sufficientheat during that time frame; however, it may also be desirable in otherapplications to continue to provide power to the heating coils throughthe pouring process to further assure no undesired solidification ofmolten metal.

FIG. 5 is a perspective cross-sectional view of an embodiment of acontrol pin 170 and spout system which may be utilized as contemplatedby this invention. FIG. 5 illustrates control pin 170 with control pinbody 142, a hollow or tubular body 142 with an internal cavity thereinand being closed at its lower end 142 c. Tubular body 142 includes lowerbody portion 142 a, and central body portion 142 b, and upper bodyportion 142 d. The upper body portion 142 d has a reduced diameter(although not necessarily required to practice embodiments of thisinvention) where the pin holder 137 (shown in other figures) operativelyattaches thereto. Control pin holder apertures 173 may be utilized tointeract with or operatively attach control pin 170 to control pinholder 137 (shown in prior figure).

While the embodiment of the control pin body illustrated includes aninternal cavity into which the heater is inserted or mounted, the terminternal cavity as used herein and in the claims may also includeembodiments wherein the heater coil or heater unit is molded into thecontrol pin body such that its outer boundaries or surfaces comprise theinternal cavity. The same use of internal cavity will be used if heaterelements are within (such as molded within) the spout (as describedbelow with respect to FIG. 7).

FIG. 5 further illustrates control pin inner cavity liner 151 withincontrol pin inner cavity 145, heating coil 143, and heating coilelectrical conductors 171. FIG. 5 also schematically shows thermocouple147 within the interior cavity 145 of control pin 170, which may beutilized for control and process purposes to monitor and control thedesired heat or temperatures. It will be appreciated by those ofordinary skill in the art that any one of a number of different typesand configurations of thermocouples may be utilized to monitor and/orcontrol the temperature which the heating coil 143 brings the controlpin to. Thermocouples may also be utilized within or near the spout orinner surface of the spout, such as the thermocouple shown in FIG. 3 asitem 152. This thermocouple may be utilized to monitor and control whenthe temperature of the style has reached a predetermined or desiredlevel for process control purposes.

Although it will be appreciated by those of ordinary skill in the artthat no particular heater element or coil is required to practice thisinvention, that a 500 Watt, 220 Volt configuration may be utilized toprovide the desired amount of heat within control pin 170. It will befurther appreciated by those of ordinary skill in the art that any oneof a number of different types of specific thermocouples may also beutilized within control pin 170 in order to monitor and control thetemperature and heat provided within control pin 170, all within thecontemplation of embodiments of this invention.

FIG. 5 also schematically illustrates controller 155 which may beutilized to receive data and control the electrical input through heatercoils 143 to reach the desired or predetermined temperature, which maybe monitored and controlled through use of one or more thermocouples 147operatively connected to controller 155. It will be appreciated by thoseof ordinary skill in the art that suitable thermocouple controllersand/or an electric heater controller, are well-known and used in the artand will not therefore be described further herein, and no oneparticular type or kind is required to practice embodiments of thisinvention.

While there is no specific portion or distance over which heat must beprovided to practice in embodiments of this invention, it may bepreferred in some embodiments to provide a heater coil and heat to thelower portion of the control pin, which may be for example the lower teninches. In the embodiment shown, the middle portion of the control pin170 may be approximately twelve inches and the top portion may bereferred to as the cold zone or top portion. It may be desirable tomaintain a certain minimum distance between the top of the control pin170 and the molten metal because the tope of the control pin 170 may bewhere wires or other connections are exposed and a minimum distance mayserve to protect or preserve those components.

In one exemplary embodiment or application, the system may preheat thecontrol pin and/or spout for approximately one hour to a temperaturewithin the control pin for example reaching nine hundred to one thousanddegrees Celsius, whereas the temperature between the outer surface ofthe control pin and the spout may be approximately four hundred fiftydegrees Celsius.

FIG. 6 is a cross-sectional view of an embodiment of a control pin 170which may be utilized as contemplated by embodiments of this invention.FIG. 6 illustrates control pin 170 represented in two sections, namelysection 6A and section 6B, which are presented in FIG. 6 forillustrative purposes and more detail. Control pin body 142 is shownwith lower portion 142 a and lower end 142 c. Control pin holderapertures 173 are shown toward the upper end of control pin 170 and areutilized to operatively attach control pin 170 to a control pin holder(not shown in FIG. 6). FIG. 6 further illustrates an exemplarythermocouple 181 with thermocouple wires 182 operatively attachedthereto and extending through the interior cavity 145 of control pin 170a controller or monitor for monitoring the temperature and increasing ordecreasing electrical input to the electrical coil to increase ordecrease the heater temperature of the exterior surface of the controlpin or of the interior surface of the spout (shown in other figures).

FIG. 6 further illustrates electrical heater coil 143 with heater coilconductor 171 operatively attached thereto and extending through theinterior cavity 145 of control pin 170. FIG. 6 also illustrates internalcavity liner 151 within internal cavity 145 of control pin 170. Theinternal liner 151 may be made of any one of a number of differentmaterials or compositions, with no one in particular being required topractice this invention. However, stainless steel may be utilized inembodiments such as those shown herein.

FIG. 6A is portion 6A from FIG. 6 of the embodiment of the control pinand spout system which may be utilized as contemplated by thisinvention. The same items referred to are numbered in a like manner andwill not be further described herein.

FIG. 6B is portion 6B from FIG. 6 of the embodiment of the control pinand spout system which may be utilized as contemplated by thisinvention. The same items referred to are numbered in a like manner andwill not be further described herein.

FIG. 7 is a cross-sectional view of an embodiment of a control systemspout which may be utilized as contemplated by this invention, whereinthe spout includes a heating element to provide heat. FIG. 7 illustratesanother embodiment of this invention wherein the heater coils 208 arecast into spout 205, or embedded therein.

FIG. 7 illustrates distribution trough 200, refractory material 201,control pin holder 204, molten metal 202, spout 205, control pin body207, control pin interior cavity liner 211, and molten metaldistribution launder framework 209. FIG. 7 also illustrates how controlpin holder 204 utilizes pins 199 inserted into control pin 207 aperturessuch as shown as items 173 in FIG. 5. Control pin holder adapter 203secures and surrounds control pin holder 204.

FIG. 7A is detail 7A from FIG. 7, and illustrates control pin 207, spout205, heater coils 208, and the arrows 210 illustrate that heater coils208 are in a circular or coiled pattern around the control pin 205.

FIG. 8 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe top portion of the spout. FIG. 8 illustrates refractory material201, molten metal 202, molten metal distribution launder framework 209,and spout 251 with spout aperture 252 through which molten metal flows.In FIG. 8 a control pin 250 with heater elements therein 248, shownattached to control pin shaft 249 (control pin shaft 249 may beconsidered part of or integral with control pin 250, or separatetherefrom). The heater 248 in control pin 250 may also be sizedsufficiently to allow sufficient transfer of heat from heater 248,through control pin body and to the upper portion of spout 251.

As will be appreciated by those of ordinary skill in the art, thecontrol pins are used to control the flow of molten metal and due tooperational issues, may not completely plug the aperture 252 in thespout 251. The control may be exerted at any location within or relativeto the spout aperture 252 in spout 251, such as at or near the top ofthe spout as shown in FIG. 8, at or near the middle portion of the spout251 (as shown for example in FIGS. 9 & 11), or at or near the lowerportion of the spout 251 (as shown for example in FIG. 10), all withinthe contemplation of embodiments of this invention.

FIG. 9 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe middle portion of the spout 251. FIG. 9 illustrates refractorymaterial 201, molten metal 202, molten metal distribution launderframework 209, and spout 251 with spout aperture 252 through whichmolten metal flows. FIG. 9 further illustrates control pin 261, controlpin shaft 260 and heater 262, with the embodiment of the control pin 261shown controlling the flow of molten metal through the spout aperture252 in spout 251 in the middle portion of the spout 251.

FIG. 10 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe lower portion of the spout. FIG. 10 illustrates refractory material201, molten metal 202, molten metal distribution launder framework 209,and spout 251 with spout aperture 252 through which molten metal flows.FIG. 10 further illustrates control pin 271, control pin shaft 270 andalso includes a heater although not specifically identified in FIG. 10,with the embodiment of the control pin 271 shown controlling the flow ofmolten metal through the spout aperture 252 in spout 251 at or near thelower portion of the spout 251.

FIG. 11 is an exemplary elevation cross-sectional view of one example ofanother embodiment of components that may be utilized in practicingaspects of this invention, showing a differently configured control pinprimarily controlling the flow of molten metal generally at or towardthe middle portion of the spout. FIG. 11 illustrates refractory material201, molten metal 202, molten metal distribution launder framework 209,and spout 251 with spout aperture 252 through which molten metal flows.FIG. 11 further illustrates control pin 281, control pin shaft 280 andalso includes a heater although not specifically identified in FIG. 11,with the embodiment of the control pin 281 shown controlling the flow ofmolten metal through the aperture 252 in spout 251 at or near the lowerportion of the spout 251.

FIG. 12 is an exemplary elevation cross-sectional view of one example ofanother embodiment of this invention illustrating heat transferrepresented by arrows 291 from the heater in the control pin 290,through the control pin body portion, and to the spout 194 by either orboth of conduction and convection, depending on the level and nature ofcontact between the outer surface of the control pin 290 and theinterior surface of the aperture 293 in the spout 251. FIG. 12 alsoillustrates refractory material 201, molten metal 202, and molten metaldistribution launder framework 209. It will be appreciated thereforethat this invention facilitates the use of either the spout body and/orthe control pin body as a heat transfer medium to transfer heat from theheater which is in the internal cavity of either the spout body or thecontrol pin body, through that body and to the body of the other (eitherthe spout body or the control pin body), to achieve the desiredpreheating of the system.

In its broadest sense, this invention would include embodiments whereinthe body of the control pin 290 is not only pre-heated itself, but isalso used as a heat transfer conduit or medium to transfer heat andthereby pre-heat the spout as well.

FIG. 13 is an exemplary elevation cross-sectional view of one example ofanother embodiment of this invention illustrating heat transferrepresented by arrows 302 from the heater 301 in the spout 300 to thecontrol pin 306. FIG. 13 also illustrates refractory material 201,molten metal 202, and molten metal distribution launder framework 209.

In its broadest sense, this invention would include embodiments whereinthe body of the spout 300 is not only pre-heated itself with heaterelements 301, but is also used as a heat transfer conduit or medium totransfer heat and thereby pre-heat the control pin 306 as well.

As will be appreciated by those of reasonable skill in the art, thereare numerous embodiments to this invention, and variations of elementsand components which may be used, all within the scope of thisinvention.

One embodiment of this invention, for example, a control pin for use incontrolling the flow of molten metal in a molten metal distributionsystem for casting is disclosed, wherein the control pin comprises: acontrol pin body with an internal cavity and an outer surface, whereinthe outer surface is sized and configured to operatively interact withan internal surface of a spout to effectively plug or control a spoutaperture; and a heater element within the internal cavity of the controlpin body. In further embodiments thereof, there may be a thermocouplelocated within the internal cavity of the control pin body to providetemperature information from within the control pin body. The controlpin referred to herein may also, in some embodiments of this invention,further be configured wherein the heater element is molded into thecontrol pin body; or wherein the control pin body is made at leastpartially of a laminated composite ceramic material that includesmultiple layers of a reinforcing fabric embodied within a cast ceramicmatrix.

In another embodiment of the invention, a preheat control system for usein a combination of a control pin and a spout used in managing moltenmetal flow from a molten metal distribution system into a casting moldis provided, wherein the preheat control system is comprised of: acontrol pin with a control pin body and an internal cavity within thecontrol pin body; a spout with a spout body and an internal cavitywithin the spout body; a heater in one of the internal cavities withinthe control pin body or in the internal cavity in the spout body;wherein heat is transferred from the heater through one of the controlpin body or the spout body, to the other one of the control pin body orthe spout body, to preheat both the control pin body and the spout body.

In yet another embodiment of the invention, a method embodiment, amethod is provided for preheating a control pin used in controlling theflow of molten metal through a molten metal distribution system and intocasting molds wherein the method comprises the following: providing aspout with a spout aperture configured to facilitate flow of moltenmetal from the molten metal distribution system into casting molds;providing a control pin body with an internal cavity and an outersurface, wherein the outer surface is sized and configured tooperatively plug the spout aperture when inserted therein; providing aheater within the internal cavity of the control pin body; inserting thecontrol pin into the spout to prevent the flow of molten metal throughthe spout; increasing the temperature of the heater within the controlpin to pre-heat the control pin prior to introducing metal to the spout;and retracting the control pin from the spout to thereby allow moltenmetal to flow through the spout. In further embodiments of theforegoing, the method may further comprise further increasing thetemperature of the heater sufficient to additionally pre-heat the spout.

In compliance with the statute, the invention has been described inlanguage more or less specific as to structural and methodical features.It is to be understood, however, that the invention is not limited tothe specific features shown and described, since the means hereindisclosed comprise preferred forms of putting the invention into effect.The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. A control pin for use in controlling the flow of molten metal in amolten metal distribution system for casting, the control pincomprising: a control pin body with an internal cavity and an outersurface, wherein the outer surface is sized and configured tooperatively interact with an internal surface of a spout to effectivelycontrol molten metal flow through a spout aperture; and a heater elementwithin the internal cavity of the control pin body.
 2. A control pin asrecited in claim 1, and further wherein a thermocouple is located withinthe internal cavity of the control pin body to provide temperatureinformation from within the control pin body.
 3. A control pin asrecited in claim 1, and further wherein the heater element is moldedinto the control pin body.
 4. A control pin as recited in claim 1, andfurther wherein the control pin body is made at least partially of alaminated composite ceramic material that includes multiple layers of areinforcing fabric embodied within a cast ceramic matrix.
 5. A heatcontrol system for use in a combination of a control pin and a spoutused in managing molten metal flow from a molten metal distributionsystem into a casting mold, the preheat control system comprised of: acontrol pin with a control pin body; a spout with a spout body; a heaterin one of the control pin body or in the spout body; wherein heat istransferred from the heater through one of the control pin body or thespout body, to the other one of the control pin body or the spout body,to preheat both the control pin body and the spout body.
 6. A method forheating a control pin used in controlling the flow of molten metalthrough a molten metal distribution system and into casting molds, themethod comprising the following: providing a spout with a spout apertureconfigured to facilitate flow of molten metal from the molten metaldistribution system into casting molds; providing a control pin bodywith an internal cavity and an outer surface, wherein the outer surfaceis sized and configured to control the opening between the spoutaperture and control pin when the control pin is inserted therein;providing a heater within the internal cavity of the control pin body;increasing the temperature of the heater within the control pin topre-heat the control pin prior to introducing metal to the spout; andpositioning the control pin into the spout to control the flow of moltenmetal through the spout.
 7. A method for heating a control pin asrecited in claim 6, and further comprising retracting the control pinfrom the spout to thereby allow molten metal to flow through the spout.8. A method for heating a control pin as recited in claim 6, and furtherincreasing the temperature of the heater sufficient to additionallypre-heat the spout.